Magnetic recording and reproducing device



N 3 H. J. HARSANT ET AL 2,658,952

- MAGNETIC RECORDINGIAND REPRODUCING DEVICE Filed May 10, 1949 3Sheets-Sheet l INVENTOR.

II THEODORE E DEUCHER HENRY J. HARSANT ATTOR Nov. 10, 1953 H. J. HARSANTETAL MAGNETIC RECORDING AND REPRODUCING DEVICE 5 Sheets-Sheet 2 FiledMay 10, 1949 INVENTOR. THEODORE F. DEUCHER' H ENRY J. HARSANT ATTO Nov.10, 1953 J, HARSANT ET AL MAGNETIC RECORDING AND REPRODUCING DEVICEFiled May lO ,1949

3 Sheets-Sheet 3 INVENTOR. THEODORE E DEUCH ER BY HENRY J. HARSANTPatented Nov. 10, 1953 ligpnf lamesrfiaggggg, Lakewood, and TheodoreFrank. Dumber-i, ka a, Qhiq, ssignor by mesnei ass gnm iils, to Ci fitct Qormmt nn C e eland; @1 10, a; mrfitign' 6 )l d T is; inventionpertaimto a ma mtie m rci andr p oducing d vi ep am mgr Eamon Iarly tosuch a ice: par eul ly aqapie i q fi u by ra io: broa c ting: st d sand: by QthQ Qrganizations or pe sa s e ir u f av ng hi h=q1i tyranscript o mac ne which 9110. v jdes bs: max mum ase nd accu cy @om troof; h i c rd; medium- It-. is an objector the-inv ion n nmv d -a hih-qual ty i ag efi qv reco ding n repliqduei devic pa t cula ly,adaptedmns ripti m 1& hich e si and q iekdy s o ds t imem- 1$ canalactiens of th opera r, A furtherobject of the in tion, is w pro deahigh-qua ity. m gnetic ramming. nd r pm u in devicewhimrespnndsitqalarg num e t 69 111 111 funct 'gna ml e hwh s relia le tsnerat n,

Another objeqt of the inventionig t =p1 ovid & high-qualitymagnetiojrecord lng and-reprgdu ing. device including a Tong Igngfih-01f, recprd ma; teria m which p o r m. materia ig ecorded} which permitSihe iifd and accurai e-looaitigniof any given portion of the, recideclpregrami.

t l another. a ect ofthe n enti n is tom-Q:- vide a. h hrquafitymagnetic. ecbrd ing nd; xe: mtqducing. d vi eh pe mits po itive andquick control f vv mi .armiv reversemqfi 'o Qt: fiha'iiecord, material.

' Another object ofthe. inventi n opmvidfei a h -qu jt magne ic wa ding.and r pz w ducing devicar wh ch may be c ntrqlled a ts. ffig lfl f cqrtrolnaneli Q1 which may, qntiollgd: at. a r mn 1 Qat 'Qn- A furtherQbjmct 0.1 the n ent bn t Q Zifde a. h h-qua ity m neticrecqidgancllrepmf. du ing de ice whqse. ecq d, materia i a Q1 matiallystopped .i'oLr allemgrge eie's excig t l lnoqr ialaspeed f iwardlmotion pasting duce'rheadis,

v ntioii', .td etmn with other andiu fi fihfire i e r n hn jq i Q cr izken. c nec'izioni wi n m n d a gs and cope wi ib 9 311 1 .1 out in' the"appended claims. l

F gv s an som tr c iew or" e mech ni a rz rtion ofthe reordererenmduceri F g: i uit idia g a j mm i sliqw qetaiis,prnorfinsmfishow; amniater ai s h as:

compfetely in" Fig; 1;" and" Fi 51 sqmetri view of. th sabinet 0. 2 tbs;dev qe,v

n Q i asp t of; th entionh f ma n tie meqre in am;- r pmdue device compes; a supp reei: ith a fiakeun e sn ced: away-fl w; itk eng-t Q1 manetic qs dmaie altfiiids b tw en th We els. and ira siiu ar head 1114m va e a d alon the m n o mQbion the recor mat ial DQEWQ Q the manl and taklr eia A; first: ecintroll bl p ivwrun t nsm tti el me t; s h= s: mai miic c utch swn ec ad. b tw en 1. t r d ivem ns and su p y r a an a 5 aQQ QQ QQBHQQJBQ between the tor li fl means-and lm was? up re fo s ee-velxqime iin the egls: in

th rm n and first and s wadrecmrol @2141 which m y -a tua d by n raqrnontm r the amfll ii of t r u an mi tad by mam-its and nqv rque:tmnwittin glem nbs t tbs: up y anq azk p ls? i i l shows th etai oriheee an aii2qi= tion bf the d mqanci, Fi z'is d ag na 9 c ic l cieuiti T mecha al ti m a jsqcia d e ectr ail; quipment a e-mumminiaq'abi'net 8! (Fig. 5) Reels 25, 26 are molmtgd; 9n the ont oft cabi ndthe ,IWQIQHJQPW- r al; 211 ext ndgf 'om me of. them ta h the gndgr thewe; 82} which encloses: thefirangdu g-e. i g he s and ridlTiYB mech n mhic is n: n gagement wi h e ecord mat ial, i A, QQ fim D In I- 83 is-v-pv ded. It ha an Gm 911' s itc and"- n s j butwns. r qntml n di ec n ndrfte m n 0i ha e erd-ma rial. Anauxiliary @o'nirei panel 83A ii proviqrd;

It i'sis'ihiilai'. in the panel a: imthe expeptign;

one reel 661116355 the supply reel and reel 26 is the takeup reel as therecord material 21 moves in a direction shown by the arrow 28 during therecording and reproducing of a program. The record material in its pathbetween the supply and takeup reels passes around a first or upper idlerroller 29, then pasta series of transducer heads such as theobliterating head 30, the recording head 3!, and the reproducing head32. The record material on its way to the takeup reel 26 then passes adriven capstan, indicated generally by the reference character 33, and asecond or lower idler roller 34.

Drive means are provided for driving the supply and takeup reels. Thedrive means comprise a clutch drive motor connected to a flywheel 36which rotates only in thev direction of the arrow 31. A belt 38 connectsthe flywheel 35 to a first controllable passive torque transmittingelement such as the magnetic clutch 39, and

a belt 48 connectsthe flywheel 36 to a second controllable passivetorque transmitting element such as the magnetic clutch 41. The belts 38and 40 are so connected to the magnetic clutches 39and GI and the recordmaterial is so wound about the reels 25 and 26 that both reels at alltimes during the operation of the device tend to wind up the recordmaterial 21. A slip ring 42 is'provided for connecting theelectromagnetic clutch 4! of the supply reel 25 to an electric circuitso that the degree of coupling of the reel 25 to the drive motor 35 maybe selectively varied in accordance with the direction and rate ofmotion of the record material and so that in an emergency the reel maybe quickly brought to a stop. The takeup reel 25 is similarly'coupled tothe drive motor 35 through the magnetic clutch 39 and the slip ring 43.Just how the clutches are controlled electrically by control means whichmay be actuated by an operator is more fully described in connectionwith the details of the electric circuit.

'A' second motor called the capstan drive motor 44 (Fig. 3) is connectedthrough a coupling collar '45 to a flywheel 45 and to a capstan drivemember or spindle 4?. The capstan drive member is adapted to be coupledto the record material at'a location between the transducer heads 30,31,32 and the takeup reel 25; A wheel 48 having a rubber tire 49 couplesthe record material 2'lto the capstan drive member 41 by pressing therecord material tightly against the capstan} andwhen so coupled thecapstan drive member-41, '47! pulls the record material past thetransducer heads. sufficiently strongly coupled to the'motor 35 by meansof the electromagnetic clutch 39 that the takeup reel 26 winds up all ofthe record material whichthe capstan drive member 41 pulls past thetransducer heads. It is preferable that the reel-26 try to take upreoordj material at a rate slightly greater than the rate at whichthe'capstan pulls it past the transducer he'adsl -The supply reel 25isvery weakly coupled to the motor 35 so that the record material ispulled from it by the capstan ll in spite of itstendency. to windjup therecord material.

A pair or tape positioning rollers 50, 55'. are provided'for positioningthe tape closely against the transducer heads only during normal-speedThe takeup reel 25 is and the tape. The rollers 50, 50 are mounted on aplate 5| which can be advanced or retracted by the screw 52, the geartrain 53, 54 and a motor 55. A second plate 65 is connected to the plate5! and carries two retracting pins 66 positioned between the tape 21 andthe obliterating head 35, preferably with one pin 65 on each side of thehead. The detailed description of the electric circuit describes how andwhen the motor is energized to advance and retract the positioningrollers 5U, 5D and the retracting pins 66 to urge the tape into closemagnetic coupling engagement with the transducer heads only duringrecording-reproducing operations and to retract the tape from theobliterating head 30 during reverse and high-speed operations. When theplates 5!, 55 are in their advanced position, the

positioning rollers 55, 50 are located between the heads 32, 3! and 3|,3!), respectively, thereby holding the tape in close operative contactwith the magnetic gap in each of the heads. In this advanced positionthe retracting pins 65 are out of engagement with the tape. When theplates 5!, 65 are in their retracted position, as shown in Fig. l, thepositioning rollers 55, 55"are away from the tape 2'! and thepositioning pins 66 engage the recording face of the tape and hold itaway from the obliterating head 38 and away from the recording head 3|.However, the tape 21 operatively engages the reproducing head 32 so thatan operator can reproduce and hear the recorded program. This feature isvaluable as it enables the operator to run the tape forward and backwardat high speed while listening for a certain portion of the recordedprogram. When the operator hears the certain portion go by, he reversesthe direction of the tape and reduces its speed. A more exact locationof the desired portion is then made.

The plate 5| to which the rollers are connected is secured to the leadscrew 52 which extends through the bifurcated mounting bracket 51mounted on the support 58. The large gear 53 is mounted between the armsof the bifurcated bracket 51, and it has a threaded hole (not shown)through which the lead screw 52extends. The spur gear 54 meshes with thelarge gear 53. The spur gear 55 and a brake wheel 58 are mounted on theshaft 55 of the motor 55 which is secured to the support 58. A brakemechanism is mounted on the'housing of the motor 55. It comprises apivotally mounted arm 6| having a frictionpad 62 underneath one of itsends in position to engage the rim of the brake wheel 59 and it has asoft iron portion 63 at its other end positioned in the field region ofthe motor 55. A spring (not shown) is connected to the mounting bracket54 for the arm 6i and engages the arm 6! to bias the friction pad 62strongly into engagement with the brake wheel 55. When the motor 55 isenergized to advance or retract the positioning rollers 56, 55 theexternal electromagnetic field of the motor attracts and holds thesoftiron portion 63 down onto the housing of the motor. therebyreleasing the frictionpad 62 from engagement with the brake wheel 59.Instantly upon the motor 55 being de-energized the friction pad 52 isspring biased into braking engagement with the brake wheel 59 to preventthe motor 55 and its gear train from coasting.

' The record material coupling wheel ples the record material to thespindle '41; of the capstan. drive memberSB in thefollowing man-- ner: Afinger 61 extends through a hole in the 43 cou-.

sweats;

mounting: bracket iii; anddszseciiiied to-the le di screw 52;. 151.181least 52: adra-i ces; the: ringer; 6,1; is: thrust: out from; the:bracket: 58s arm flit is piyotally: mounted at: 69; fin 'l'lfii bra ket;58; and. one: of: its, ends. is; connected o a; strong: spring; ML Thecoupling; wheel; 4-8: is rotatahiitmounted on. the. otherend; (iii the.arm. E8; The; Spring. 10:. enga es aspin H extending upifrom; the finger617a. the finger" E1; is; drineni ionwatdthaarmfifi pivotsahout; point.69 untilithet rubber tire. 45s of the coupling Whfifill 418; n agestheatape-Zt at the location at the spindle 4172.01; the: capstan 33;.'Iihsfinger; 61: continuesttobe; driven; forward and& the: spring: 730bends; as the; arm: 58-: cannot: pivotlany: furtherrduemoathe' whe l;dabeing hards against the tape 2] whiciriszbaokeili thei capstan;spindle.- 411;. This establishestai strong spring biascontinuonslyiurging the; (101111. pling wheel; 48; against; the; capstan spindle; 45with the: tape. 2-:7, pinched; between;

A switch actuating; plate. 12; issecured to the; bottom. of. the fingen6:1 ande advances: re tracts. with. it. Underneath. the; switohi actuaatin'g plate 12 and. carried, by; it: are, four inclinedi switch.actuating, blocks: 13 (only: twirshowmi which engage and; depress thepins; it. (only one shown) of: the; Inicro=switches 15;, 116;; Pb, 1Bias the plate Hi advances. The; inclined; faces: of: the four switchactuating; blocks 13a are; so; positioned with respect to the; switchpins Hi; that; the switches: are-actuated at: different times. therebyintroducing time; delay in a; seriesofg switchingoperations, more.fully-i described; in connection; with; the eleotricala circuit;

. A .lower'tapezbrealcswitchi!)lgisdocatedlbetween;

the. capstan 33: and: the takeup reel lfiiand; come-- prises the; idlerroller.- SA: about which the recordmaterial: 21.: runs therebyscausingithe capstanfiitotrotateb A shaftjifi; is oonneetedi 110111.61 cape stan;and a cupzshapedz member 351 18. .Sfi0111'fidi to: the shaft. and. theyboth rotate. with; the; capstan. Within" the cup shaped. memhenwith;,one; face; bearing against the; bottom writer-cc; thereof; isa;frictionpad, and aiplateiiscoonneetediaroundzthei shatt: 36.; and-hearsagainst the; otheis face: 01;

the; friction. pad. At pin isrconne ted: to; the; pl t and. extends;outwardly: beyond:the;- lip .Qi-i he-icun-shaped member WhB z it looselyen es he; switch; actuatin arms .9, of; the; switch". 92 Whem thecrecorder neproducer; is, eithen r cor s insiproeram; on is.reproduoineia previous y recorded: program; the. magnetiorecordimember:ravelsfitom thesupplyreel; 2.5 ItrQithQl takeup; reel; 25.; and c u es;the idler. roller 5 5 rotate ina; olockwisedirectiom Thisirotates heduprshapedi member in a: clockwise.- direotion: and: throu h: he fictionpad. there ni appl es aas: whieh' loses the-cswitehi 92:. Theswitch 9.2; s; held; losed so] one: astheidler ll r. is bei turn d: by;the r eord: ma eri l; bu immediately upon: h idler'roi er 3A1 c asin to,turn ither; dueto. a: br ak-a e; of" the res-0rd: mater al. to: a deliberate stopping of the machine, the frictional bias home ed from the; swtch 9.2; andtitiopensup.

.eniunp n p reak sw tch: I'M-i. lfiii silocated; bet ee th supp y:T931115 and the const. 3.5;: It m ri es he i ler ro ler-2.9 which wen:

a. lo -w e. dire tion; by therecdrdrmateriai; lur n t srecordine: and.playb ck onerationsn The idler lle 9- s m nt d.- on; ne; nd i: a; haf Ere; 4;) and dn vep a e: QI-iSjtiEh Y connected: to the 1 h r end .o zezshaftn Aieun- 1 hap d member 9.5, is; mounted; around. the; sha t:9.3; hr mea s Q e:bear na se and: t e haft: ad to a e-c with-1 respect;o;v

; bothitheendof themotor shaft l- -l-fl andthejow has two. portions 41,41-! of; difierent diamete p a srotatect brdl rr llerz a tri'ctionekforce is; appl e o the cup shapedi member 95 causing; it to, rotatain;the samedirection; d r ro l r- A. pin 98; is qnn ctedz to the: 0119shaped: em er 1: upon: rota-hem of; 111193611129.

' h med: me ber engages: ne or theother: of: two;

w ch: err-ms 99; and I00, dependin on: he: t i n OI. rota ion, the: twards-or: resend ns and re ntro u in direction. the; him-9&1, ens e sessw tch; arm -fl tand? clo es switch; Hz. This ri tiona bias p lied,to..- switch I01: through w h; a m 1. 39;, pin: 95; and; iipsshapf dmembsn k eps switc clos d. so lone: as: the idler: rol er E0tat. n minBtGlQQkWEfiidil'fifibiOh; he idiot oll r stops; due; to: any cause the:ion lib as: is emoved findi theifiontactsi switshi LL pen, Rotation. ofthe idler 11011.81? 29; ima: counter-clockwise direction; causes the";pirr-v 98a to; engage switch arm 99 to close switch IE2; and: sta lishan: ectrical: holdin ope ati n ii j is describeddetail; in, connectionwith-they elect-s riscire it I The? 033 314; assernblm. which is:indicated: gen-s 6. 4136 by: the reference; Qhanacten-Sit, isiconsieeed? to, the m u tinsrbracket; 58.: by means: of? the split ring I03which is integraliwith on con, nected; to; the mounting bracket 511s.vhollow shaft 04- is mounted: within the split ringsllm nd; h rin is:clamped; to; the shaft I581 bw tightening; the screw. [0.5;The-uppenendiof the- 1 hollow shaft. M14: is: closed by; ineanspof a.large-:-

screw I96, and; a bearing (-nota shown-h pros-ivided: between, thatupper end, of the; rotatable; pindle 4i and t'hfii shaft 11114. Near the11131357. end; of; the hollow'shatt l llslsthere isra windows leliwhiehexposes-both a small, diameter 41: and; a large; diameter 46! portionof: the rotatable; spindle so that it,mayi he ooupledtotthe-recordmember 2], by means, of; the! eoupling wheel 48.

The spindle 41' (Fig. 3) of the capstan assembly 33 is connected tothemotor 44 by means of the sleeve 45.. which is indriving, engagementtwiththe shaft I I 0, of] the, motor Within the sleeyedfi; there, is-arubbercollar l l land thisirubben-co an is intight frictional. dr vin agement:W

end. of. the spindle. Both the motonshaftian the spindle may beknurledtrortkeyed atthe: lee t on of the-rubber collar to provide goodfriction gripping The spindle which drives the tape,

exposedat the window I01. Either ofthesetwo; portions, may be coupledto: the tape 21 so that the. tape. may be, driven at two, diiferentspeeds, When, the smaller diameter portion 41 of; h spindleengages the;tape-, the tape. is. driven e; an a.., slower speed thanwhenthelargediameter 012- tionJ'I! isinengagementwith thetape; ,7 V or; position;one onthe other-0f. the spind. ipsr qnsi L1, 41. next toithe; tape 2-1the entire; spindle as sembly is moved. The, collars2 4 5; and;the-rubber: coupler H I, should: be; sufiiciently long that thmcapstantassembly as maybe slidtlongitudinal with respect: tothe split.ring H13ito positio t large diameter portion 47:"ofthe spindle opposithe-location of the couplingwheellflp- I 'IZhis;- -.p vides two-speeddrive of the record materials order to change-the drivespeed thefscrewlqfi ist loosened: and the entire assembly, comprising the hollow-[shaftI114; therspindle-l4ilr-withinsthe;

thei 7.;5; haft and h fiywheeLAli-is m rednntihthe otherg 7 diameterportion of the spindle is opposite the coupling wheel 43. The screw I05is then tightened. Longitudinal slippage of the spindle 41 with respectto the motor shaft is permitted by the rubber collar III within thesleeve 45.

The electrical circuit of the relay system which operates the recorderdevice is connected to a source II5 of 110 volt alternating current.Through an on-ofl switch H6 and fuses II], III the current source II5energizes the primary of the power transformer H8. The secondary of thetransformer is fused by fuses I19, H9. The output of the transformer H8is rectified by a dry disk rectifier system I20 to furnish 14 voltsdirect current across the line I2I, I22. The 110 volt A. C. circuit isconnected across lines I23, I24 and energizes the drive motor 35 for theclutches 39, M and reels 25, 26 and also energizes the drive motor 44for the capstan 33. Through the rectifier I25 in the A. C. line I23 andthe resistors I26, I21, D. C. power is supplied to energize the takeupand supply reel clutches 39 and M Closing the on-off switch IIB alsoimmediately applies a slight D. 0. potential through slip rings 43 and42 to the magnetic clutches 39, 4I thereby tending to cause the reels26, 25 connected to the clutches to take up tape. This applies a slighttension to the portion of the tape 21 extending between the two reels.

Closing the on-ofi switch H3 also energizes the D. C. line I2I, I22 andthrough the upper tape break switch IOI, I02 energizes the relays I5 andII. This causes relay contacts I 3-I and III to close. Closing thecontacts IB-I and II-I immediately energizes relay I! which closes acontact in the playback amplifier I8 thereby muting the amplifier. Themuting is released when the tape starts to move opening the upper tapebreak switch IDI, I52 which de-energizes relay I causing switch Ill-I toopen and break the circuit through muting relay I'I.

SEQUENCE OF OPERATION.

Playback operation The operator selects the desired operation, such asplaybackfby pushing the Play button I9. This energizes relay coil 6.Relay holds itself in through its own contact 6-I and also closescontact 6-2 and contact 6-3 in the circuit of relays 3 and 3A. Then theoperator presses the start button 20. 'This energizes start relay I2from the line I22 through closed contact 62 and through the closedcontact I2-I which was closed when the start button 29 was pushed, andback through closed contacts I5I and II-I to negative line I2 I. RelayI2 holds itself in through contact I2I after the start button isreleased. Relay I2 closes contact I22 to energize line I23 and closescontact I2-3 to energize line I23. As soonas line I28 becomes energized,relays 3 and 3A are energized through closed contact 6'-3 back to thenegative line I33. Relay 3, when energized, makes a circuit for relay I3from line I22 through line I3I, closed contact" 15, closed contact 3I,the field coil 55' of the motor 55 and closed contact 3-2. Relay I3closes the switch- I3--I which energized a muting relay I'I in-theplayback amplifier I8 and maintains the muted condition until motor 55positions the capstan coupling wheel 48 and the rollers 59, 53",

at which time the switch I3I opens.

Relay I3 also closes contact l3--2 to energize relay I6. Relay I5 closesthe contact I6-I to establish a circuit through the armature of motor 55to cause the capstan idler 48 to engage the tape and push it against thedrive capstan 41 and also to position the rollers 50, 50'. A closedcontact I6 mounted on the pressure pad assembly opens as the motor 55advances the plate I2, causing the motor 55 to stop when the finger 61reaches the end of its stroke. Operation of motor 55 causes contact TIto close and this through closed relay contacts Ill-2 energizes thetakeup clutch 39. As the tape starts to move, the lower tape-breakswitch 92 is closed, shunting relay contacts IIl2 which open as the tapeis underway. The purpose of this circuit through contact 92 is to permitthe machine to continue operating if the tape breaks between the takeupreel and the capstan but it also de-energizes the takeup reel clutch 39in case of a break so that the tape on the takeup reel will not bethrown around. As the tape starts moving, the line I28 is held in thecircuit by the upper tape break switch contact IBI which keeps relay 3energized even though the start relay I2 falls out when relay It becomesale-energized and contact IIl-I opens.

To stop the above sequence, the operator presses the Stop button 2|which energizes relay I4 and closes contact I4I thereby energizing relay4. Relay i is held by contact 4I and through closing contact 42 itenergizes relay I. Relays I and 4 make a circuit through contacts I--Iand 43 from the positive D. C. line I32 through the back contact ofrelay 5-4 and energize the supply reel clutch M which tends to bring thetape to a stop. Relay 4 simultaneously de-energizes relay 6 by openingcontact 44 and relay 6 de-energizes relays 3 and 3A by opening contact3-3. De-energizing relay 3 starts the capstan idler motor 55 to operateby returning contacts 3-I and 3-2 and brings the capstan idler wheel48away from the capstan 33 and also removes the pressure rollers 53, 50from between the transducer heads 32, 3| and 3|, 30 respectively.Running the motor 55 to put the finger 61 in its retracted positionthrows contact I8 during fast forward and fast reverse motion of therecord material to prevent the program recorded on the record materialfrom being heard in a distorted manner. The amplifier is also in a mutedcondition while the record material is standing still to preventpush-button or switching noises from being heard as an operator puts themachine in condition to operate. The amplifier is not muted duringnormal speed forward and reverse motion of the record material undercontrol of the program locator push-buttons I35, I35 as it is essentialthat the operator hear the program being reproduced in order for him toexactly locate the desired portion of the recorded program.

The muting circuit for the push-pull playback amplifier I8 comprises arelay I! for shorting the grids of the last stage of the amplifier bymeans of switch'blade' I'I-I. One side of the relay is connected topositive and the other side is connected to negative through switchI3'-I of relay I3 and through switches I-2, 2-2, and l52 of relays I, 2,and I5, respectively. a When the on-ofi switch I I6 is closed and thestart button 20 is pushed relay blades IIlI and III are thrown, as hasbeen described. When the magnetic record material is at rest. switchesI2,

escapee v 2-2, and I-2 are on their back contacts and connect the relayI! through closed contacts III-.1 and I I-l to the negative side of anelectric circuit thereby energizing-the relay I1 and actuating theSwitchblade I "I-I which immediately shorts the playback amplifier.

The capstan idler motor 55 is energized to cause the coupling roller 49to engage the capstan spindle 41 and to cause the rollers 50, to pressthe tape 'ZI against the transducer heads. As the switch actuating plate"I2 moves forward simultaneously with the actuation of the couplingroller 48, it actuates the switches 19 and 16.

Switch I9- energizes relay I5 which opens switch blade I5-2 in themuting circuit. Substantially Record operation The sequence of theoperation of the relays in the record cycle is somewhat similar to thatin the playback cycle, the difference being that the record amplifierplate voltage is energized during recording but not in playback.

When the record button 22 is pressed, relay 9 becomes energized, whichcloses contacts 9-2 paralleling contacts 6-3 thereby energizing relay 3.Contacts 9-4 of relay 9 close energizing relay 9A, and relay 9A holdsitself in through its own contacts 9A-I and. I5-I which closes when themotor starts to run and closes contact 19. Relay 9A also closes itscontacts 9A-2 to ener- .gize the plate voltage-of the record amplifier23. All other operations are the same as in the play sequence. When theunit is stopped from the record operation, contacts I 5-l of relay I5continue to hold in relay 9A. This keeps plate voltage on the recordamplifier 23 until the tape has been removed from the record and eraseheads so that noises will not be recorded on the tape due to transientsset up by braking of the positive circuit to the record amplifier. Relay9A de-energized when the motor .55 retracts the idler i 48 and opens theswitch ;I9, thereby opening switch contacts I5-I.

During the stop part of the record cycle, it is necessary to remove thetape from the regard and erase head before tie-energizing the platevoltage of the record amplifier. This is accomplished by holdi l y 9 hih is ener ized through contact 9-4 to close contact 9A-I and contactI5-I is held closed until the motor ,55 has retracted, opening thecontact [9.

Fast forward operation is controlled through pushbutton 24' called FastForward. Qlosing the button 24 energizes relay I which holds itself n yclosing nta t 'I.l- .R la also closes contact 1-2 making a circuit fromline I28 through the relay I to negative line I311, and also closescontact 'I-3 so that pressing thestart but.- n 20 energizes the l e 1.28throu h contac 12-2 of relay I2. This energizes relay I whi h closes itscontact l-I to make a circuit from the D. C. 110 volt positive controlline 132 through the takeup reel clutch 39. To stop the fast forwardoperation, the stop button'ZI is pressed, which energizes relay I4closing contact I4-I to energize relay I. This closes contact 4-3 andcloses contact 8-3.

10 switches the feed of D. C. from the takeup reel clutch to the --supply-reel clutch 4| andbringsj the tape to a stop. As soon as the tapecomes to a stop, the upper tape break switch I01 opens, deenergizingrelay '4 and which in turn tie-energizes the supply reel clutch II. v

The rewind operation is controlled by the re.- wind pushbutton 56 whichenergizes relay 8. Relay =8 holds itself in through its own contact 8-Iand also contacts 3-3, I4- '2, and 5-2 of relays 3; I I, and 5,respectively. The holding circuit for relay 8 includes contact .3-3 ofplayback relay '3. The reason for holding relay :8 thr u h r ay i at thperator mig t 11 advertent l-y select both forward and reverse. If hethen pushed the start button the record medium would try to go bothforward and reverse at the same time. With'contact 3-3 in the circuit ofrewind relay :3 both operations cannot be simultaneously selectedbecause energizing playback relay .3 opens contact 3-3 in the holdingcircuit thereby de.-energizing relay 8. Eel-ay 8 closes contact 8-2 toestablish a circuit through relay -2 to negative line I30 and alsoPressing the start button 26 energizes relay I12 which energizes relay2. Relay 2 .cioses contacts 2-I .to energize the supply reel clutch IIwhich drives the tape in the rewind direction. As soon as the tape is inmotion, reiay "2 is held in by the upper tape break switch I62. Therewind operation is stopped by pressing the stop button '2 I whichenergizes relay I..4 and also relay 5. Relay 5 holds itself in byclosingwcontact 5-3 and it reverses the feed from the supply reel clutchto the takeup reel clutch by closing contact 5.-l causing the tape tocome to a stop. As soon as the tape is stopped, the upper tape breakswitch I 92 will open deenergizing relays 5 and 2 and leaving the systemde .-.energized.

In the fast =forward or fast reverse directions either relay I or 2is'energized thereby throwing either switch I-2 or 2-2 to bypass theopen switch 43-.1 thereby muting the playback amplifier I8 even thougheither switch 'I 0-1 or -II..:I is .open. When the operator-is actuatingforward pushbutton'1'35 orreverse pushbutton 136 of the program locator,the muting is removed by one .or :the other of the relays I0, all being-.de.-energi-zedby-the tape break switches 92 or IIII. 'This openseither switch Ill-I or II-I as has been explained.

Locating a particular program on the tape is .done by means of theforward and rewind program locator buttons I35, I36. These buttonsdirectly energize whichever clutch 39, II is chosen to drive the tapeforward or rewind at a reasonably high rate of speed. This is effectedby the chosen switch shunting out the 15,000 .ohm resistor I26 or I21 tothe selected clutch, thereby strongly energizing that clutch; Actuatingof the program locator buttons also removes the muting from the playbackamplifier I6 so that the operator can hear the program being reproducedfrom the portion of the record material going through the playback head.This permits the operator to adjust the position of the tape accuratelyfor radio broadcasting programs and the like.

A forward limit switch I56 and a reverse limit switch ar provided. Thesear associ ted with a timing device (n Shown having a forward directionlimit hand and a reverse direction limit hand whose positions aremanually adjustable. A timer is provided having a hand or pointer whichis geared to the tape drive mechanism. The pointer rotates in aclockwise direction as the tape moves forward, and when the pointerengages the forward direction limit hand the forward limit switch I40 isclosed energizing relay 4 to stop the tape, as has previously been morefully described in connection with stopping the tape by pushing the stopbutton 2 I.

When the tape is moving in the reverse direction the pointer moves in acounter-clockwise direction until it engages the adjustable reversedirection limit hand. This closes the rewind limit switch MI energizingrelay which holds itself in by contact 5-3. Relay 5 throws the contact5--I thereby substantially de-energizing the supply reel clutch 4|PROTECTIVE CIRCUITS A 15,000 ohm resistor I26, 121 is connected inseries with each reel clutch to excite each reel clutch slightly therebyto cause a slight tension to be exerted on the tape at all times toprevent forming of loops. The forward and rewind program locator buttonsI35, I36 short-out the 15,000 ohm resistors when in operation. A circuitis made by relay 3A through relay contact 3A-I to prevent the prematureoperation of clutch 39 through contact I 5I at the start when the rewindlimit switch has operated.

A 25 ohm resistor I31 is placed in series with the capstan drive motor44 to reduce its speed when running in the play position to aid in thereduction of mechanical noise. This resistor is controlled by thecontact I8 of the capstan idler motor assembly. In case of a tape breakbetween the supply ree1 25 and the capstan '33 in the play position,relay 3 is immediately de-energized, running the capstan idler assemblyback to its restricted position. If in the "play position the tapeshould break between the capstan 33 and takeup reel 26, the machine willcontinue to operate normally with the exception that the tape beingpulled through the capstan will run on the floor rather than coil up onthe takeup reel. Due to the operation of the lower tape break switch 92the stron energization of the clutch 39 is removed leaving only theslight tensioning energization. This causes the takeup reel 26 to rotateslowly.

In case of a tape break in the fast forward operation the upper tapebreak switch IOI will open, de-energize relay I, which opens contact I-Ito de-energize the takeup clutch 39 and the system will coast to a stop.In the fast rewind operation breakage of the tape will cause the uppertape break switch I02 to de-energize relay 2 which opens contact 2I totie-energize the supply reel clutch 4i permitting the system to coast toa stop.

While there have been described what are at present considered to be thepreferred embodiments of this invention, it will be obvious to thoseskilled in the art that various changes and modifications may be madetherein without departing from the invention, and it is, therefore,aimed in the appended claims to cover all such cahnges and modificationsas fall within the true spirit and scope of the invention.

What is claimed is:

1. In a device for moving filamentary record material: a supply reel, atakeup reel spaced away from said supply reel with a length of saidrecord material extending between said supply reel and said takeup reel;motor drive means including only a single motor, first electricallyenergizable passive torque transmitting means connected between saidmotor drive means and said supply reel for selectively coupling saidsupply reel to said motor drive means, first electric control meansconnected to said first torque transmitting means and actuable by anoperator for energizing said first torque transmitting means with afixed amount of electric current which is invariable throughout the timeof said control action controlling the amount of torque transmitted bysaid first passive torque transmitting means from said motor drive meansto said supply reel, second electrically energizable passive torquetransmitting means connected between said motor drive means and saidtakeup reel for selectively coupling said takeup reel to said motordrive means, second electric control means connected to said secondtorque transmitting means and actuable by said operator for energizingsaid second torque transmitting means with a fixed amount of electriccurrent which is invariable throughout the time of said controlledaction controlling the amount of, torque transmitted by said secondpassive torque transmitting means from said motor drive means to saidtakeup reel.

2. A device for moving filamentar record material as set forth in claim1, further characterized by second unidirectional motor drive meansincluding a unidirectionaly driven capstan, and movable coupling meansfor selectively coupling said capstan to said record material at alocation between said two reels.

3. A device for moving filamentary record ma terial as set forth inclaim 2, further characterized by said first and second control meanscontrolling the said coupling means to cause said capstan to be coupledto said record material during forward motion of said record material ata given speed, and to cause said capstan to be decoupled from saidrecord material during forward and rewind motion of said record materialat a speed substantially greater than said given speed.

4. A device for moving filamentary record material as set forth in claim3, further characterized by record material positioning means actuableby said control means, said positioning means holding said recordmaterial against said transducer head means during forward motion atsaid given speed and being spaced away from said record material duringforward and rewind motion of said record material at said substantiallygreater speed.

5. A device for moving filamentary material as set forth in claim 4,further characterized by said filamentary material comprising amagnetizable record track and by magnetic transducer head means beinglocated along the path of motion of said record material at a pointbetween the said supply reel and the said capstan.

6. In a device for moving filamentary material: a supply reel, a takeupreel spaced awa from said supply reel, a length of filamentary materialextending between said supply reel and said takeup reel, drive meansincluding a motor-driven capstan and a coupling roller for coupling saidfilamentary material to said capstan for driving said filamentarymaterial in a forward direction; electrically'driven means connected tosaid coupling roller for moving said coupling roller into engagementwith said filamentary material and for pressing said filamentarymaterial against said capstan; an idler roller located along the path ofmotion of said filamentary material between said supply reel and saidcapstan and driven by said filamentary material, switch means connectedin the circuit of said electrically driven means; friction meansfrictionally biased by said idler roller only during rotation of saididler roller and in contact with said switch means for applying africtional bias to hold said switch means in a given position to causesaid coupling means to couple said filamentar material to said capstanonly during rotation of said idler roller.

7. A device for moving filamentary material as set forth in claim 6further characterized by said coupling roller including a motor and bysaid switch means in a position other than said given positionenergizing said motor to cause said coupling roller to move away fromsaid filamentary material to decouple said filamentary material fromsaid capstan.

8. In a device for moving filamentary material: a supply reel, a takeupreel spaced away from said supply reel, means including an electricallycontrolled passive torque transmitting element for driving said takeupreel, a length of filamentary material extending between said supplyreel and said takeup reel, drive means including a motor driven capstanand coupling means for coupling said filamentary material to saidcapstan for driving said filamentary material; an idler roller locatedalong the path of motion of said material between said capstan and saidtakeup vice: a supply reel, a takeup reel spaced away from said supplyreel, a length of magnetic record material extending between said supplyreel and said takeup reel, means for driving said record material inforward or reverse directions; first operator actuated control means forcontrolling the means for driving said record material forward, secondoperator actuated control means for controlling the means for drivingsaid record material in reverse, and selection means interconnectingsaid first and second control means, said selection means including aswitch in the second control means and means in said first control meansfor opening said switch when said record member is moving forward sothat upon an operator substantially simultaneously actuating both ofsaid control means only one of said control means becomes effectivewhereby substantial driving forces in only one direction are imparted tosaid record material.

HENRY JAMES HARSANT. THEODORE FRANK DEUCHER.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,051,787 Foster Aug. 18, 1936 2,106,730 Foster Feb. 1, 19382,314,834 Kiel Mar. 23, 1943 2,365,691 Fodor Dec. 26, 1944 2,408,320Kuhlik Sept. 24, 1946 2,418,541 Camras Apr. 8, 1947 2,419,476 Begun Apr.22, 1947 2,464,220 Duncan Mar. 15, 1949 2,467,507 Stone Apr. 1, 19492,469,706 Winther May 10, 1949 2,500,903 Nefi Mar. 14, 1950 2,501,573McLouth Mar. 21, 1950 2,535,486 Dank Dec. 26, 1950 2,540,299 Shoup Feb.6, 1951 FOREIGN PATENTS Number Country Date 459,035 Great Britain Dec.31, 1936

